Study the Effect of Ruthenium Dye Layer on Negative Capacitance in Solar Cells Based on the Nc-TiO₂ Semiconducting Polymer Heterojunction

H. Al-Dmour

Department of Physics, Faculty of Science, Mu'tah University, Mu’tah, Jordan.

DOI: 10.4236/msa.2015.61012                

Abstract

We report the effect of ruthenium dye on negative capacitance of nanocrystalline titanium dioxide/poly(3-hexyl thiophene), nc-TiO₂/P3HT, heterojunction solar cells. It has been found that the low frequency capacitance reaches a high positive value and then drop to the negative region. In P3HT/Ru-Dye/nc-TiO₂ solar cells, the negative capacitance is observed under very low forward bias condition unlike the negative capacitance in P3HT/ncTiO₂ solar cells. That is attributed to the difference of the concentration of dipole and presence of depletion region at interface between the P3HT and nc-TiO₂.

Keywords

Admittance Spectroscopy, Negative Capacitance, Forward Bias, Polarization

Conflicts of Interest

The authors declare no conflicts of interest.

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